Isolation of recombinant apolipoprotein E4 N-terminal domain by foam fractionation.

Apolipoprotein (apo) E functions in lipoprotein metabolism as a low density lipoprotein receptor ligand. ApoE is comprised of two structural domains, a 22 kDa N-terminal (NT) domain that adopts a helix bundle conformation and a 10 kDa C-terminal domain with strong lipid binding affinity. The NT domain is capable of transforming aqueous phospholipid dispersions into discoidal reconstituted high density lipoprotein (rHDL) particles. Given the utility of apoE-NT as a structural component of rHDL, expression studies were conducted. A plasmid construct encoding a pelB leader sequence fused to the N-terminus of human apoE4 (residues 1-183) was transformed into Escherichia coli. Upon expression, the fusion protein is directed to the periplasmic space where leader peptidase cleaves the pelB sequence, generating mature apoE4-NT. In shaker flask expression cultures, apoE4-NT escapes the bacteria and accumulates in the medium. In a bioreactor setting, however, apoE4-NT was found to combine with gas and liquid components in the culture medium to generate large quantities of foam. When this foam was collected in an external vessel and collapsed into a liquid foamate, analysis revealed that apoE4-NT was the sole major protein present. The product protein was further isolated by heparin affinity chromatography (60-80 mg/liter bacterial culture), shown to be active in rHDL formulation, and documented to serve as an acceptor of effluxed cellular cholesterol. Thus, foam fractionation provides a streamlined process to produce recombinant apoE4-NT for biotechnology applications.

Cardiac-specific deficiency of 3-hydroxy-3-methylglutaryl coenzyme A lyase in mice causes cardiomyopathy and a distinct pattern of acyl-coenzyme A-related biomarkers.

Deficiency of 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) lyase (HL) is an autosomal recessive inborn error of acyl-CoA metabolism affecting the last step of leucine degradation. Patients with HL deficiency (HLD) can develop a potentially fatal cardiomyopathy. We created mice with cardiomyocyte-specific HLD (HLHKO mice), inducing Cre recombinase-mediated deletion of exon 2 at two months of age. HLHKO mice survive, but develop left ventricular hypertrophy by 9 months. Also, within minutes after intraperitoneal injection of the leucine metabolite 2-ketoisocaproate (KIC), they show transient left ventricular hypocontractility and dilation. Leucine-related acyl-CoAs were elevated in HLHKO heart (e.g., HMG-CoA, 34.0 ± 4.4 nmol/g versus 0.211 ± 0.041 in controls, p < 0.001; 3-methylcrotonyl-CoA, 5.84 ± 0.69 nmol/g versus 0.282 ± 0.043, p < 0.001; isovaleryl-CoA, 1.86 ± 0.30 nmol/g versus 0.024 ± 0.014, p < 0.01), a similar pattern to that in liver of mice with hepatic HL deficiency. After KIC loading, HMG-CoA levels in HLHKO heart were higher than under basal conditions, as were the ratios of HMG-CoA/acetyl-CoA and of HMG-CoA/succinyl-CoA. In contrast to the high levels of multiple leucine-related acyl-CoAs, biomarkers in urine and plasma of HLHKO mice show isolated hyper-3-methylglutaconic aciduria (700.8 ± 48.4 mmol/mol creatinine versus 37.6 ± 2.4 in controls, p < 0.001), and elevated C5-hydroxyacylcarnitine in plasma (0.248 ± 0.014 µmol/L versus 0.048 ± 0.005 in controls, p < 0.001). Mice with liver-specific HLD were compared, and showed normal echocardiographic findings and normal acyl-CoA profiles in heart. This study of nonhepatic tissue-specific HLD outside of liver reveals organ-specific origins of diagnostic biomarkers for HLD in blood and urine and shows that mouse cardiac HL is essential for myocardial function in a cell-autonomous, organ-autonomous fashion.

Nearshore bathymetry and seafloor property studies from Space lidars: CALIPSO and ICESat-2.

In shallow nearshore waters, seafloor heights and properties can be accurately measured by the current generation of space-based elastic backscatter lidars: CALIOP, flying aboard the CALIPSO satellite and ATLAS aboard ICESat-2. CALIOP's 532 nm volume depolarization ratios, together with the ratios of the attenuated backscatter coefficients measured at 532 nm and 1064 nm, can efficiently distinguish optically shallow waters from nearby land surfaces and deep oceans. ATLAS's high vertical resolution photon measurements can accurately determine seafloor depths in shallow water bodies, characterize seafloor reflectance, and provide assessments of ocean biomass concentrations in the intervening water column. By adding bathymetry, seafloor optical properties (e.g., reflectance, depolarization ratio and attenuated backscatter), and nighttime observations, space lidar measurements obtained in nearshore waters can provide a wealth of unique information to complement existing satellite-based ocean color remote sensing capabilities. The results reported here demonstrate the feasibility of using satellite lidars for nearshore seafloor ecosystem analyses, which in turn provide critical insights for studies of coastal navigation and seabed topography changes due to disasters, as well as the temporal and spatial morphological evolution of coastal systems.

Open-label follow-on study evaluating the efficacy, safety, and quality of life with extended daily oral immunotherapy in children with peanut allergy.

BACKGROUND: The benefit of daily administration of Peanut (Arachis hypogaea) Allergen Powder-dnfp (PTAH)-formerly AR101-has been established in clinical trials, but limited data past the first year of treatment are available. This longitudinal analysis aimed to explore the impact of continued PTAH therapeutic maintenance dosing (300 mg/day) on efficacy, safety/tolerability, and food allergy-related quality of life. METHODS: We present a subset analysis of PALISADE-ARC004 participants (aged 4-17 years) who received 300 mg PTAH daily for a total of ~1.5 (Group A, n = 110) or ~2 years (Group B, n = 32). Safety assessments included monitoring the incidence of adverse events (AEs), accidental exposures to food allergens, and adrenaline use. Efficacy was assessed by double-blind, placebo-controlled food challenge (DBPCFC); skin prick testing; peanut-specific antibody assays; and Food Allergy Quality of Life Questionnaire (FAQLQ) and Food Allergy Independent Measure (FAIM) scores. RESULTS: Continued maintenance with PTAH increased participants' ability to tolerate peanut protein: 48.1% of completers in Group A (n = 50/104) and 80.8% in Group B (n = 21/26) tolerated 2000 mg peanut protein at exit DBPCFC without dose-limiting symptoms. Immune biomarkers showed a pattern consistent with treatment-induced desensitization. Among PTAH-continuing participants, the overall and treatment-related exposure-adjusted AE rate decreased throughout the intervention period in both groups. Clinically meaningful improvements in FAQLQ and FAIM scores over time suggest a potential link between increased desensitization as determined by the DBPCFC and improved quality of life. CONCLUSIONS: These results demonstrate that daily PTAH treatment for peanut allergy beyond 1 year leads to an improved safety/tolerability profile and continued clinical and immunological response.

trans-3-Methylglutaconyl CoA isomerization-dependent protein acylation.

3-methylglutaconic (3MGC) aciduria is associated with a growing number of discrete inborn errors of metabolism. Herein, an antibody-based approach to detection/quantitation of 3MGC acid has been pursued. When trans-3MGC acid conjugated keyhole limpet hemocyanin (KLH) was inoculated into rabbits a strong immune response was elicited. Western blot analysis provided evidence that immune serum, but not pre-immune serum, recognized 3MGC-conjugated bovine serum albumin (BSA). In competition ELISAs using isolated immune IgG, the limit of detection for free trans-3MGC acid was compared to that for cis-3MGC acid and four structurally related short-chain dicarboxylic acids. Surprisingly, cis-3MGC acid yielded a much lower limit of detection (∼0.1 mg/ml) than trans-3MGC acid (∼1.0 mg/ml) while all other dicarboxylic acids tested were poor competitors. The data suggest trans-3MGC- isomerized during, or after, conjugation to KLH such that the immunogen was actually comprised of KLH harboring a mixture of cis- and trans-3MGC haptens. To investigate this unexpected isomerization reaction, trans-3MGC CoA was prepared and incubated at 37 °C in the presence of BSA. Evidence was obtained that non-enzymatic isomerization of trans-3MGC CoA to cis-3MGC CoA precedes intramolecular catalysis to form cis-3MGC anhydride plus CoASH. Anhydride-dependent acylation of BSA generated 3MGCylated BSA, as detected by anti-3MGC immunoblot. The results presented provide an explanation for the unanticipated detection of 3MGCylated proteins in a murine model of primary 3MGC aciduria. Furthermore, non-enzymatic hydrolysis of cis-3MGC anhydride represents a potential source of cis-3MGC acid found in urine of subjects with 3MGC aciduria.

Coenzyme Q nanodisks counteract the effect of statins on C2C12 myotubes.

Depletion of coenzyme Q (CoQ) is associated with disease, ranging from myopathy to heart failure. To induce a CoQ deficit, C2C12 myotubes were incubated with high dose simvastatin. This resulted in a concentration-dependent inhibition of cell viability. Simvastatin-induced effects were prevented by co-incubation with mevalonic acid. When myotubes were incubated with 60 µM simvastatin, mitochondrial CoQ content decreased while co-incubation with CoQ nanodisks (ND) increased mitochondrial CoQ levels and improved cell viability. Incubation of myotubes with simvastatin also led to a reduction in oxygen consumption rate (OCR). When myotubes were co-incubated with simvastatin and CoQ ND, the decline in OCR was ameliorated. The data indicate that CoQ ND represent a water soluble vehicle capable of delivering CoQ to cultured myotubes. Thus, these biocompatible nanoparticles have the potential to bypass poor CoQ oral bioavailability as a treatment option for individuals with severe CoQ deficiency syndromes and/or aging-related CoQ depletion.

Recent Developments at the CMA: 2020-2021.

We discuss three important projects that economists at the Competition and Markets Authority have completed over the past year. First, our work on the Funerals Market Investigation provides an illustration of how demand-side problems can lead to a lack of competition, as well as demonstrating the CMA's willingness to consider price control and regulatory remedies where necessary. Second, on the Sabre/Farelogix merger case, we point to how our assessment dealt with uncertainty in innovative markets, the importance of preventing incumbents from acquiring start-ups, and the risks of following formalistic market definitions, especially in multi-sided platform sectors. Third, we set out the most notable developments in our revised Mergers Assessment Guidelines-including the assessment of future competition even when subject to significant uncertainty-and the assessment of the loss of dynamic competition and its effect on innovation incentives.

Incidence of Anicteric Veno-Occlusive Disease/Sinusoidal Obstruction Syndrome and Outcomes with Defibrotide following Hematopoietic Cell Transplantation in Adult and Pediatric Patients.

Veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is a potentially life-threatening complication of hematopoietic cell transplantation (HCT) that is traditionally diagnosed using Baltimore or modified Seattle criteria. Whereas the Baltimore criteria require the presence of hyperbilirubinemia (bilirubin ≥2 mg/dL) for a diagnosis of VOD/SOS, the modified Seattle criteria do not. Before approval by the US Food and Drug Administration, defibrotide was available in the United States through an expanded-access study (T-IND). The T-IND protocol initially required post-HCT diagnosis of VOD/SOS by the Baltimore criteria or biopsy but was later amended to include patients diagnosed using the modified Seattle criteria. This post hoc analysis examined the incidence of VOD/SOS with a bilirubin level <2 mg/dL before and after Day 21 post-HCT in T-IND patients enrolled following the amendment allowing for diagnosis by the modified Seattle criteria. Survival of adult and pediatric patients with or without hyperbilirubinemia and with or without multiorgan dysfunction (MOD) was also evaluated. Of 803 post-HCT patients with VOD/SOS enrolled following the protocol amendment, 181 (23%) had a bilirubin level <2 mg/dL and would not have been diagnosed if hyperbilirubinemia was required. The bilirubin level at diagnosis was <2 mg/dL in 165 of 331 patients (50%) diagnosed by the modified Seattle criteria and in 16 of 23 patients (70%) diagnosed by biopsy. VOD/SOS with a bilirubin level <2 mg/dL was more common in pediatric patients (29%), although it also occurred in adult patients (15%). Patients with hyperbilirubinemia had lower Day 100 survival (54% versus 87% in patients with bilirubin <2 mg/dL) and a higher incidence of MOD (41% versus 26% in patients with bilirubin <2 mg/dL). The incidence of treatment-emergent adverse events and serious adverse events was lower in patients with a bilirubin level <2 mg/dL. These results indicate that anicteric VOD/SOS occurs in both adult and pediatric patients post-HCT and can be diagnosed before and after Day 21 in both groups. The worse survival in patients with bilirubin ≥2 mg/dL suggests that requiring hyperbilirubinemia may result in a progressed disease stage associated with worse outcomes. Taken together, these results highlight the importance of awareness and the possibility of VOD/SOS in the absence of elevated bilirubin level.

Pooled analysis of Day 100 survival for defibrotide-treated patients with hepatic veno-occlusive disease/sinusoidal obstruction syndrome and ventilator or dialysis dependence following haematopoietic cell transplantation.

For patients with untreated hepatic veno-occlusive disease (VOD)/sinusoidal obstruction syndrome (SOS) with multi-organ dysfunction (MOD), mortality is >80%. We conducted a pooled analysis of three studies that assessed Day 100 survival in relationship to MOD severity, with dialysis and/or ventilator dependence representing the most severe organ dysfunction. All patients in the analysis were diagnosed using Baltimore criteria/biopsy. This analysis of patients with VOD/SOS and MOD after haematopoietic cell transplantation (HCT; n = 651) demonstrated higher Day 100 survival rates amongst defibrotide-treated patients with VOD/SOS with less versus more severe forms of MOD. Even patients with severe forms of MOD post-HCT benefitted from defibrotide.

Peanut allergy impact on productivity and quality of life (PAPRIQUA): Caregiver-reported psychosocial impact of peanut allergy on children.

BACKGROUND: Limited research has examined the impact of peanut allergy (PA) on children using validated instruments to assess psychosocial burden and the factors influencing burden. OBJECTIVE: The PAPRIQUA study aimed to assess the caregiver-reported impact of living with PA on children's health-related quality of life (HRQL), correlations between PA severity and child's sex, and associations of caregivers' sex and anxiety with the proxy report of their child's HRQL and to identify significant predictors of a child's HRQL. METHODS: A cross-sectional survey of caregivers of children with mild, moderate and severe PA, based on caregiver perception, was conducted in the United Kingdom. Participants were recruited through a survey recruitment panel; a maximum quota of 20% who rated their child's PA as mild was set to ensure population diversity; however, the quota was not required as few participants considered their child's PA mild. The survey, funded by Aimmune Therapeutics, included sociodemographic and clinical questions, the EQ-5D-Y, Hospital Anxiety and Depression Scale, Food Allergy Quality of Life Questionnaire-Parent Form (FAQLQ-PF) and Food Allergy Independent Measure (FAIM). RESULTS: One hundred caregivers of children with PA (aged 4-15 years) completed the survey. Child's sex was not associated with proxy-reported burden. For younger children (aged 4-10 years), there was no effect of PA severity; parents of older children (aged 11-15 years) reported low to higher burden for their child on the EQ-5D-Y and FAQLQ-PF dependent upon PA severity. For all measures of child burden except the EQ-5D-Y, two or more reactions in the past 12 months and parental anxiety significantly predicted higher levels of burden for the child (P < .05-P < .001). Experiencing a life-threatening event in the past 12 months significantly predicted EQ-5D-Y proxy utility (P < .01). CONCLUSIONS AND CLINICAL RELEVANCE: Caregivers report that children with PA experience high levels of psychosocial burden, particularly those with more severe PA and a reaction history. Interventions to decrease caregiver anxiety and reaction frequency may help reduce the child's burden. Self-report studies in children with PA would help confirm these findings.

APPEAL-2: A pan-European qualitative study to explore the burden of peanut-allergic children, teenagers and their caregivers.

BACKGROUND: Allergy to Peanuts ImPacting Emotions And Life (APPEAL-1) was a recent European multi-country questionnaire survey that highlighted the negative impacts of peanut allergy (PA) on quality of life. A follow-on qualitative study, APPEAL-2, further assessed the burden of PA and associated coping strategies through semi-structured interviews. OBJECTIVE: To gain qualitative insight on the strategies used to cope with and manage PA and the impact of these strategies on the quality of life of children, teenagers and caregivers. METHODS: This cross-sectional qualitative study was conducted in eight European countries: the United Kingdom, France, Germany, Ireland, Spain, Italy, Denmark and the Netherlands. Semi-structured interviews were conducted with children (aged 8-12 years) and teenagers (aged 13-17 years) with self-/proxy-reported moderate or severe PA and with parents/caregivers of children or teenagers (aged 4-17 years) with moderate or severe PA. Data were analysed using thematic analysis; data saturation was assessed. Two conceptual models were developed to illustrate the impacts of PA and coping strategies used to manage them for (a) individuals with PA and (b) parents/caregivers of children with PA. RESULTS: 107 participants were interviewed: 24 children, 39 teenagers and 44 caregivers. The conceptual models illustrated themes related to coping and control, driven by the fear of PA reactions, and the associated emotional, social, relationship and work impacts. Factors moderating these impacts included social attitudes and support, child-caregiver relationship and coping strategies used. CONCLUSIONS AND CLINICAL RELEVANCE: The APPEAL-2 results substantiate the findings of APPEAL-1; the results also suggest that the severity of experience with PA may not correlate with perception of its overall burden and show variable impacts by country.

APPEAL-1: A multiple-country European survey assessing the psychosocial impact of peanut allergy.

BACKGROUND: Peanut allergy (PA) is a common, potentially life-threatening and typically lifelong condition with a significant burden of illness. However, information is lacking on how persons with PA (PwPA) and their caregivers perceive the psychosocial impact of living with PA. The Allergy to Peanuts imPacting Emotions And Life 1 (APPEAL-1) survey, conducted across Europe, investigated the experience and impact of living with PA. Here, we report data evaluating the psychosocial impact of PA on PwPA and their caregivers. METHODS: Allergy to Peanuts imPacting Emotions And Life study 1 was an online survey conducted in eight European countries. Representatives of eight patient advocacy groups and five healthcare-research specialists developed the survey. Eligible respondent groups included the following: adults diagnosed with PA (self-report); parent/nonparent caregivers (proxy-report for a child with PA); and parent/nonparent caregivers (self-report of PA impact on themselves). RESULTS: Of 1846 total study respondents, 419 were adults with PA (self-report); 546 were parents/caregivers (proxy-report); and 881 were parents/caregivers (self-report). Most respondents reported lifestyle restrictions regarding food (84%-93%) and additional domains including parties and socializing, holiday activities and destinations, and taking public transport (53%-89%). Approximately 40% rated themselves as "very" frustrated and "very" stressed. Two-thirds (65%) felt socially isolated; 43% were bullied. Less than half felt confident in knowing when to use an adrenaline autoinjector. Several intercountry differences were observed such as high levels of uncertainty and stress in respondents from Ireland, highest rates of anxiety in respondents from Germany, and social exclusion and isolation most common in respondents from France. CONCLUSIONS: Peanut allergy imposes an adverse psychosocial impact on patients and caregivers, leading to frustration, stress and isolation. Attention to the impact of PA is needed in research and clinical practice to improve PA healthcare and public education programmes.

APPEAL-1: A pan-European survey of patient/caregiver perceptions of peanut allergy management.

BACKGROUND: Peanut allergy (PA) is associated with marked quality-of-life (QoL) impairment. However, data are lacking on the experience and impact of living with PA from the perspectives of persons with PA (PwPA) and their caregivers. Allergy to Peanuts imPacting Emotions And Life study 1 (APPEAL-1) was a pan-European survey investigating these perspectives. This first of two articles reports clinical characteristics of PwPA and PA management practices. METHODS: APPEAL-1 was a quantitative, online survey conducted in eight European countries, developed by eight representatives of patient advocacy groups and five healthcare professionals and researchers. Eligible participants included adults with PA and parents/caregivers of PwPA who responded by self-report and provided proxy-report for the PwPA under their care. Data were summarized using nonweighted descriptive statistics. RESULTS: Of 1846 completed/analysed questionnaires, 528 were from adults with PA (self-report); 437 by proxy for children with PA (34 aged 0-3 years, 287 aged 4-12 years, 116 aged 13-17 years) and 881 from parents/caregivers (self-report). Of PwPA (N = 965), 95% reported diagnosis by healthcare professionals, mostly by clinical history and peanut-specific allergy testing. Rates of allergic rhinitis, asthma and other food allergies in PwPA were 50%, 42% and 79%, respectively. Only 31% of PwPA received HCP advice/support following their worst allergic reaction, and 28% had not been prescribed an adrenaline auto-injector. Results were similar by country but varied by age group. CONCLUSIONS: The APPEAL-1 findings contribute to greater understanding of PA impact on PwPA, caregivers and family members and the need for improved PA management across Europe.

Dye binding assay reveals doxorubicin preference for DNA versus cardiolipin.

Doxorubicin (DOX) is a potent anticancer agent that binds both DNA and cardiolipin (CL). To investigate DOX binding to CL versus DNA, aqueous soluble, CL-enriched nanoparticles, termed nanodisks (ND), were employed. Upon incubation with CL-ND, but not with phosphatidylcholine ND, DOX binding was detected. DOX binding to CL-ND was sensitive to buffer pH and ionic strength. To investigate if a DOX binding preference for DNA versus CL-ND exists, an agarose gel-based dye binding assay was developed. Under conditions wherein the commercial fluorescent dye, GelRed, detects a 636 bp DNA template following electrophoresis, DOX staining failed to visualize this DNA band. Incubation of the template DNA with DOX prior to electrophoresis resulted in a DOX concentration-dependent attenuation of GelRed staining intensity. When the template DNA was pre-incubated with equivalent amounts of free DOX or DOX-CL-ND, no differences in the extent of GelRed staining intensity attenuation were noted. When DOX was incubated with DNA alone, or a mixture of DNA and CL-ND, the extent of DOX-induced GelRed staining intensity attenuation was equivalent. Thus, DOX has a binding preference for DNA versus CL and, moreover, DOX-CL-ND offer a potential strategy to prevent DOX-induced cardiotoxicity while not affecting its affinity for DNA.

Effectiveness and Safety of Intrathecal Ziconotide: Final Results of the Patient Registry of Intrathecal Ziconotide Management (PRIZM).

BACKGROUND AND OBJECTIVES: The Patient Registry of Intrathecal Ziconotide Management evaluated the long-term effectiveness and safety of intrathecal ziconotide. METHODS: The study was a prospective, multicenter observational study of intrathecal ziconotide in US clinical practice. Patients were adults with severe chronic pain that warranted intrathecal therapy. Ziconotide was initiated as the single agent in the pump; however, other intrathecal medications were permitted. The primary efficacy outcome was ≥30% reduction in numeric pain rating scale score from baseline at week 12. A secondary outcome was patient global impression of change. Adverse events were solicited at each visit. RESULTS: The registry enrolled 93 patients. Seventy-four and 28 patients completed 12 weeks and 18 months of treatment, respectively. In the overall patient population, 17.4% had ≥30% pain reduction from baseline at week 12, with a mean reduction in pain of 10.9%. At month 18, 38.5% of patients had ≥30% pain reduction from baseline, with a mean pain reduction of 24.7%. Patient-rated improvement was reported in 67% of patients at week 12 and 71% at month 18. Almost all patients experienced adverse events, the most common of which were nausea (25.8%), confusional state (22.6%), and dizziness (20.4%). CONCLUSIONS: Final study analyses showed that intrathecal ziconotide provided clinically meaningful pain relief in 17.4% and 38.5% of patients at week 12 and month 18, respectively. At these same time points, patient-rated improvement was reported in at least two-thirds of patients. The safety profile was consistent with that listed in the ziconotide prescribing information.

High density lipoprotein promotes nascent apolipoprotein A-V secretion from mRNA transfected cells.

Despite its exceptionally low circulating concentration, apolipoprotein (apo) A-V is a potent modulator of plasma triacylglycerol levels. The secretion efficiency of nascent apoA-V was investigated in cultured cells transfected with mRNA. Following transfection of HepG2 cells with wild type apoA-V mRNA, apoA-V protein was detectable in cell lysates by 6 h. At 24 h post transfection, evidence of apoA-V secretion into media was obtained, although most apoA-V was recovered in the cell lysate fraction. By contrast, apoA-I was efficiently secreted into the culture medium. A positive correlation between culture medium fetal bovine serum content and the percentage of apoA-V recovered in conditioned media was observed. When transfected cells were cultured in serum-free media supplemented with increasing amounts of high density lipoprotein, a positive correlation with apoA-V secretion was observed. The data indicate that, following signal sequence cleavage, the bulk of nascent apoA-V remains cell associated. Transit of nascent apoA-V out of cultured cells is enhanced by the availability of extracellular lipid particle acceptors.

Correction to: Sphingadienes show therapeutic efficacy in neuroblastoma in vitro and in vivo by targeting the AKT signaling pathway.

The authors would like to note an omission of disclosure in this paper. Author JDS is cofounder, equity-holder, and consultant of GILTRx Therapeutics.

Data Products, Quality and Validation of the DLR Earth Sensing Imaging Spectrometer (DESIS).

Imaging spectrometry from aerial or spaceborne platforms, also known as hyperspectral remote sensing, provides dense sampled and fine structured spectral information for each image pixel, allowing the user to identify and characterize Earth surface materials such as minerals in rocks and soils, vegetation types and stress indicators, and water constituents. The recently launched DLR Earth Sensing Imaging Spectrometer (DESIS) installed on the International Space Station (ISS) closes the long-term gap of sparsely available spaceborne imaging spectrometry data and will be part of the upcoming fleet of such new instruments in orbit. DESIS measures in the spectral range from 400 and 1000 nm with a spectral sampling distance of 2.55 nm and a Full Width Half Maximum (FWHM) of about 3.5 nm. The ground sample distance is 30 m with 1024 pixels across track. In this article, a detailed review is given on the applicability of DESIS data based on the specifics of the instrument, the characteristics of the ISS orbit, and the methods applied to generate products. The various DESIS data products available for users are described with the focus on specific processing steps. The results of the data quality and product validation studies show that top-of-atmosphere radiance, geometrically corrected, and bottom-of-atmosphere reflectance products meet the mission requirements. The limitations of the DESIS data products are also subject to a critical examination.

Sphingadienes show therapeutic efficacy in neuroblastoma in vitro and in vivo by targeting the AKT signaling pathway.

Neuroblastoma is a childhood malignancy that accounts for approximately 15% of childhood cancer deaths. Only 20-35% of children with metastatic neuroblastoma survive with standard therapy. Identification of more effective therapies is essential to improving the outcome of children with high-stage disease. Sphingadienes (SD) are growth-inhibitory sphingolipids found in natural sources including soy. They exhibit chemopreventive activity in mouse models of colon cancer, where they mediate cytotoxicity by inhibiting key pro-carcinogenic signaling pathways. In this study, the effect of SD on neuroblastoma was analyzed. Low micromolar concentrations of SD were cytotoxic to transformed and primary neuroblastoma cells independently of N-Myc amplification status. SD induced both caspase-dependent apoptosis and autophagy in neuroblastoma cells. However, only inhibition of caspase-dependent apoptosis protected neuroblastoma cells from SD-mediated cytotoxicity. SD also inhibited AKT activation in neuroblastoma cells as shown by reduced phosphorylated AKT levels. Pre-treatment with insulin attenuated SD-mediated cytotoxicity in vitro. SD-loaded nanoparticles (NP) administered parenterally to immunodeficient mice carrying neuroblastoma xenografts resulted in cytotoxic levels of SD in the circulation and significantly reduced tumor growth compared to vehicle-treated controls. Analysis of tumor extracts demonstrated reduced AKT activation in tumors of mice treated with SD-NP compared to controls treated with empty NP. Our findings indicate SD are novel potential chemotherapeutic agents that promote neuroblastoma cell death and reduce tumorigenicity in vivo.

Cardiolipin and mitochondrial cristae organization.

A fundamental question in cell biology, under investigation for over six decades, is the structural organization of mitochondrial cristae. Long known to harbor electron transport chain proteins, crista membrane integrity is key to establishment of the proton gradient that drives oxidative phosphorylation. Visualization of cristae morphology by electron microscopy/tomography has provided evidence that cristae are tube-like extensions of the mitochondrial inner membrane (IM) that project into the matrix space. Reconciling ultrastructural data with the lipid composition of the IM provides support for a continuously curved cylindrical bilayer capped by a dome-shaped tip. Strain imposed by the degree of curvature is relieved by an asymmetric distribution of phospholipids in monolayer leaflets that comprise cristae membranes. The signature mitochondrial lipid, cardiolipin (~18% of IM phospholipid mass), and phosphatidylethanolamine (34%) segregate to the negatively curved monolayer leaflet facing the crista lumen while the opposing, positively curved, matrix-facing monolayer leaflet contains predominantly phosphatidylcholine. Associated with cristae are numerous proteins that function in distinctive ways to establish and/or maintain their lipid repertoire and structural integrity. By combining unique lipid components with a set of protein modulators, crista membranes adopt and maintain their characteristic morphological and functional properties. Once established, cristae ultrastructure has a direct impact on oxidative phosphorylation, apoptosis, fusion/fission as well as diseases of compromised energy metabolism.